The default view settings in Microsoft 365 Outlook are slightly different from Outlook 2019. After your system is upgraded, follow the steps below to move your Outlook apps and display the classic ribbon.
Move the apps (Mail, Calendar, People, etc.) from the left navigation to the bottom navigation.
- Select File.
- Select Options under the Info tab. Then, select Advanced (3) and uncheck the Show Apps in Outlook box (4).
- Select OK and restart Outlook.
Switch to Classic Ribbon
By default, the Simplified Ribbon is selected in Microsoft 365 Outlook. To change this to the Classic Ribbon, select the down caret.